1. Technical Field
The present invention relates to a structure of mounting a fan to a fan motor used for cooling a radiator or air-conditioner, for example.
2. Description of the Prior Art
Referring to FIG. 3, the conventional electric motor fan has a fan-mounting seat structure wherein a plurality of thrust washers 5 are fitted into a tip section supported on a casing 1 through a bearing 3 and a flat washer 7 is thrust on a peripheral surface of a smaller diameter step formed on the tip section. However, since the thrust washer 5 is made of a thin plate, the outermost thrust washer 5 located opposite to the flat washer 7 may be mounted in the state that it is departed from the smaller diameter step. This drawback can be prevented when mounting the thrust washers 5. Yet, since a motor shaft 2 provides such small play as allowing its travel to the shaft core, at a stage of fastening a fan boss with a nut after mounting the thrust washers 5 safely, the motor shaft 3 may be slipped (that is, the motor shaft 2 is moved from the rightmost thrusting state as shown in FIG. 3 to the leftmost state where the left end of the motor shaft is pressed on a casing bottom), thereby often causing the thin tabular thrust washer 5 to fall onto the small diameter section. In this state, if the fan is installed thereto, the fan does not match to the core of the motor shaft, resulting in causing adverse effects on smooth rotation of the fan and drawbacks such as vibrations or abnormal wear on a bearing.